$\dfrac{4}{3} - \dfrac{4}{2} = {?}$
Answer: $ = {\dfrac{4 \times 2}{3 \times 2}} - {\dfrac{4 \times 3}{2 \times 3}} $ $ = {\dfrac{8}{6}} - {\dfrac{12}{6}} $ $ = \dfrac{{8} - {12}}{6} $ $ = -\dfrac{4}{6}$